Discussions

News: WSTL Studio announced: Web Services based on JSP tag libraries

  1. WSTL Studio is a development environment that allows development of JSP Tag Libraries based on Web services. It utilizes Java Script for tag logic and makes Web services accessible as objects in the script.

    The whole process of creation of Web services based tags does not require routine work of writing Web services invocation Java code and can be done using wizards and Java Script. That allows Web developers using Web services in their JSP pages without in-depth knowledge of WSDL, SOAP and Java programming.

    WSTL Studio is based on the Eclipse platform and Apache Axis. The current milestone build is available as a standalone application for three platforms: MS Windows, Linux and MacOS X. In the near future, it will be available as Eclipse plug-in too.

    http://www.wstl.net – WSTL Studio Web site

    http://www.wstl.net/tutorials.jsp - Example demonstrating usage of Amazon.com Web services in WSTL Studio
  2. A DHTML client for WSDL is an impressive feat indeed. Or according to a CalTech dude recently:

    "The simplicity of XMLRPC made it possible to write the browser client in Javascript running inside a browser. This would not be possible with SOAP due to its complexity."

    -- http://www.ppdg.net/archives/ppdg-idat/2003/msg00186.html
  3. Sounds interesting. I did not dig deep into the tutorials. But, tried the demo (Amazon WS). It seems there are some unhandled errors. Try searching with keyword that is too obvious to be not found. I tried ""Here comes an error"".
  4. Pretty interesting. From the tutorials, it looked like it integrated into Eclispe, no? Or is it it's own standalone IDE?

    I wonder about the choice of using Javascript for the tag handler logic. Most server side J2EE is Java. Nonetheless, it looks pretty easy to use.

    Joe Pardi
    dotJ Software
    http://www.dotjonline.com
  5. Joe,

    You are right. WSTL Studio is integrated into Eclipse.
    Current build is available only as a standalone application, but with the next build it will also be available as separate Eclipse plug-in.
  6. Server side javascript (ECMA script) is not part of the J2EE spec... and though it appears both IBM and BEA support it, I am somewhat doubtful that support should be counted on. Until recently I thought it died with Netscape Enterprise server, but then I read that Websphere supports it... Now I did some googling and find that BEA does as well... Why anyone would write to such a proprietary server extension when plain java is a well defined standard, is broadly supported and not significantly more complicated than javascript is beyond me.

    Anyone who has ever written javascript for both IE and Netscape knows that every javascript implementation ever produced is laden with a vast number of quirks and proprietary extensions. These make it completely non-portable and therefore an extremely poor choice of programming language.

    Now the whole web services based on JSP taglibs sounds interesting... just can the server side javascript..... please.
  7. Chris,

    You are talking about support of Java Script by IBM, BEA, Netscape and others.
    Support of Java Script what for?
    I can assume that you mean the usage of Java Script as a scripting language for scriptlets in JSP pages, but WSTL does not force you to use other scripting language in JSP instead of Java (although J2EE specification does support other scripting languages in JSP scriplets).
    WSTL Studio uses Java Script for tag handler logic and on the output it generates Java classes that can be used in any J2EE application server regardless whether does it support Java Script or not. All JSP implicit objects such as session, request, response, pageContext, etc. are accessible from Java Script as well as from Java.

    Usually Web developers are not familiar with Java programming, tag handlers and especially with the usage of WSDL/SOAP in Java. Although in most cases they even don’t need to write Java Script code to create a tag invoking Web service because WSTL Studio generates it automatically using wizards.

    "Anyone who has ever written javascript for both IE and Netscape knows that every javascript implementation ever produced is laden with a vast number of quirks and proprietary extensions."
    As I mentioned before WSTL does not have any relation with Java Script running in a browser. Nevertheless, I think insisting that particular scripting language is poor because different browser implementations have incompatible set of objects, is not right.

    David.
  8. SSJS is extinct.[ Go to top ]

    So, can you tell me what version of server-side javascript any of the application server vendors use? Can you tell me where is the documentation for the exact language specification they support? The example in the tutorial on WSTL uses Amazon.com, so I took the liberty of searching Amazon.com for "server-side javascript". I got 2 hits, one book from 1997 and one book from 1999. I found this review of one of the books quite telling:

    "The book was very good with the best history of JavaScript (server and client-side) I have ever read. However, nobody in the professional world will start a project today in SSJS, the language is extinct. Only legacy web applications will be using this and there are so many better server-side languages available now."

    That pretty much sums up my feeling on SSJS. Just forget about it. It confuses the otherwise interesting WSTL greatly. Most developers (web or otherwise) consider JavaScript a client-side scripting language. The smart ones know that it is a double-edged sword on the client... allowing one to perform validations and other client-side magic without a network round-trip, at the cost of dangerous risk of bugs and client-side variations that tightly controlled server back-ends are not subject to.

    While WSTL is intersting and is a nice effort to simply the task at hand, plese, put away the hype. Page 5 of 6 of the Amazon.com tutorial here http://www.wstl.net/tutorials/amazon/step5.jsp contains a full page of SSJS code. This flatly contradicts the statement in the overview section of http://www.wstl.net/ that "The whole process does not require any programming. ".

    Javascript is quite a complex language in its own right, with many, many flaws. Stating that it is not "programming" is flat-out wrong.

    An example using JSP scriptlets would be quite welcome.
  9. RE: SSJS is extinct.[ Go to top ]

    While WSTL is intersting and is a nice effort to simply the task at hand, plese, put away the hype. Page 5 of 6 of the Amazon.com tutorial here http://www.wstl.net/tutorials/amazon/step5.jsp contains a full page of SSJS code. This flatly contradicts the statement in the overview section of http://www.wstl.net/ that "The whole process does not require any programming. ".

    To create custom tag that invokes Web service and puts the result to session or page context, developer does not need to write any code. This is the purpose of WSTL Studio (there is no hype here). Then the result can be processed using third-party tag library such as Jakarta Taglibs, <display:*> tag library or any other.
    However, developers still have ability to extend tag’s logic using statements like “if”, “for”, “while”, etc. in the same manner as they do in client-side Java Script in HTML pages (this is optional and is not required in most cases).
    The tags (nextPage and prevPage) on page 5 of the tutorial are given on purpose for not to use particular third-party taglib in the tutorial.
    In WSTL Studio, Java Script is used only for a trivial task of calling Web service as an object and in most cases the code generated by WSTL Studio should not be modified at all.
    I think there is misunderstanding of the purpose of Java Script in WSTL Studio.
    It is not a tool for development of server-side J2EE applications. It is a tool for creating custom tags invoking Web services.

    So, can you tell me what version of server-side javascript any of the application server vendors use? Can you tell me where is the documentation for the exact language specification they support?

    Personally, I have never been interested in the usage of Java Script in JSP scriplets and as I mentioned it has no connection with the purpose and the way in which Java Script is used in WSTL.
  10. But, tried the demo (Amazon WS). It seems there are some unhandled errors.

    The demo is not supposed to be a real application. We tried to keep it as simple as possible to make it readable and easy to understand. Therefore it does not have error handling and extra features.
  11. Brian,

    WSTL does not have any relation with DHTML and Java Script running inside a browser. It is a tool for developing server-side JSP Tag Libraries that can be deployed to J2EE application server.

    I agree with you that using WSDL/SOAP in browser Java Script is not a good idea.

    What WSTL does, it allows converting Web Services to Java Script (server-side Java Script) objects, in the same manner as Apache Axis does for Java.

    "This would not be possible with SOAP due to its complexity."

    I do not see anything impossible to invoke Web services as objects from Java Script.

    David.
  12. MY EYES!![ Go to top ]

    AAAHH!@!!
  13. WSTL Studio is a development environment that allows development of JSP Tag Libraries based on Web services. It utilizes Java Script for tag logic and makes Web services accessible as objects in the script.

    The whole process of creation of Web services based tags does not require routine work of writing Web services invocation Java code and can be done using wizards and Java Script. That allows Web developers using Web services in their JSP pages without in-depth knowledge of WSDL, SOAP and Java programming.

    WSTL Studio is based on the Eclipse platform and Apache Axis. The current milestone build is available as a standalone application for three platforms: MS Windows, Linux and MacOS X. In the near future, it will be available as Eclipse plug-in too.

    http://www.wstl.net – WSTL Studio Web site

    http://www.wstl.net/tutorials.jsp - Example demonstrating usage of Amazon.com Web services in WSTL Studio